Adjusting Generator 3rd Brush

C

chrismac52

Member
For Christmas I received a Voltage Regulator to replace the cutout on my generator on my 36 ford. Looking at the generator I "think" I know which brush to push, but I thought I would ask before I got too carried away. Can anyone explain to me the proper way to make the adjustment or even better yet have a picture? I have never messed around with generators before.

Thanks!
 
On my 36 only one brush moves, the others and the third move but only to compensate for wear on the brush. I may be wrong 50/50 chance but if I remember right to increase output rotate the brush in the direction the generator turns. If your amp gauge is working set the engine at about 2000 rom and turn the lights on and move the brush untill you just get a positive charge and you should be good. Others may correct me and shouldif this is not right.
 
I installed the generator and adjusted the 3rd brush, however no matter how far i advance the 3rd brush it shows 0 to barely charge at fast idle with lights turned off and still a large discharge with the lights on. Anyone have any experience with these Voltage Regulators (B-10505-V8) or can provide any advice?
 
While I have no experience with these solid state replacements, the problem seems more likely to be with the generator itself. Did you have the same problem with the old cutout?

Jack E/NJ
 
With the old cutout it would show a good charge (10 to 15 amps) at fast idle without the lights on. So I think the generator should be ok.
 
I haVE the cut out regulator on my 35 and it works great. I have a radio and it also works fine. Send me contact info if I can help.
 
If you are adjusting the brush with the new solid state regulator installed, you won't show much of a discharge or charge unless your battery is really low and requires charge from the generator (this is because the regulator is working!) You need to adjust the brush for the proper voltage level from the generator according to the instructions which hopefully came with your regulator. (all this is assuming you have one of the new solid state regulators)
 
I show a large discharge when I have the lights on instead of a slight charge like the directions show. It is new purchased from Macs.
 
Big fast-idle discharge with the lights on, suggests the new cutout may be faulty assuming the 3rd brush is in the max charge position.

Jack E/NJ
 
I agree with Jack, if it worked OK before with the cutout then it's probably not the generator. Unless you have access to a good ammeter and voltmeter its pretty hard to diagnose. Any possibility you have a short when you turn the lights on?
 
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I put the cutout back on and it still doesn't seem to be charging right. Something bad must happened when I adjusted the brush. So I will go from there.

Thanks guys!
 
Here's a real low tech test for the gen, I do it a lot, on new rebuilt, (or old used) to see if it's going to work...
Hook the generator up to a battery like it's a motor, I would use positive ground, you can use 12v... Hook up the negative cable to the wires leading right out of the generator... The generator should spin, "motor" if it's working... Oh, yeah-take off the fan belt-
Karl
 
Chrismac, make sure the third brush didn't get pulled out part way in its holder, sometimes they stick.
 
The quickest way to tell if its charging with the lights on is to use a volt meter on the battery. It should stay at 7 to 7.5 volts whether the lights are on or off. Adding a voltage regulator to a gen that was a 3-brush set up kind of adds one more thing to go wrong. A generator wound for a 2-brush set up usually is more reliable with a solid state voltage controler. Keep in mind it now has a diode to eleminate the cut out, a voltage regulation circuit, and some form of a current limiting circuit or at least it should have. Your amp meter becomes a charge meter more or less.
 
From its description, I don't think this solid state cutout regulates the field coils as a true voltage regulator for a 2 brush generator would. Accordingly, it probably functions like the old mechanical point cutout albeit faster and still requires manual adjustment of the third brush.

Jack E/NJ
 
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